Abstract

Multiple lines of evidence support the pathogenic role of neuroinflammation in psychiatric
illness. While systemic autoimmune diseases are well-documented causes of neuropsychiatric
disorders, synaptic autoimmune encephalitides with psychotic symptoms often go under-recognized.
Parallel to the link between psychiatric symptoms and autoimmunity in autoimmune diseases,
neuroimmunological abnormalities occur in classical psychiatric disorders (for example,
major depressive, bipolar, schizophrenia, and obsessive-compulsive disorders). Investigations
into the pathophysiology of these conditions traditionally stressed dysregulation
of the glutamatergic and monoaminergic systems, but the mechanisms causing these neurotransmitter
abnormalities remained elusive. We review the link between autoimmunity and neuropsychiatric
disorders, and the human and experimental evidence supporting the pathogenic role
of neuroinflammation in selected classical psychiatric disorders. Understanding how
psychosocial, genetic, immunological and neurotransmitter systems interact can reveal
pathogenic clues and help target new preventive and symptomatic therapies.